patch-2.4.22 linux-2.4.22/arch/mips64/kernel/time.c

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diff -urN linux-2.4.21/arch/mips64/kernel/time.c linux-2.4.22/arch/mips64/kernel/time.c
@@ -1,9 +1,10 @@
 /*
  * Copyright 2001 MontaVista Software Inc.
  * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
+ * Copyright (c) 2003  Maciej W. Rozycki
  *
  * Common time service routines for MIPS machines. See
- * Documents/MIPS/README.txt.
+ * Documentation/mips/time.README.
  *
  * This program is free software; you can redistribute  it and/or modify it
  * under  the terms of  the GNU General  Public License as published by the
@@ -17,10 +18,12 @@
 #include <linux/sched.h>
 #include <linux/param.h>
 #include <linux/time.h>
+#include <linux/timex.h>
 #include <linux/smp.h>
 #include <linux/kernel_stat.h>
 #include <linux/spinlock.h>
 #include <linux/interrupt.h>
+#include <linux/module.h>
 
 #include <asm/bootinfo.h>
 #include <asm/cpu.h>
@@ -28,9 +31,14 @@
 #include <asm/hardirq.h>
 #include <asm/div64.h>
 
-/* This is for machines which generate the exact clock. */
-#define USECS_PER_JIFFY (1000000/HZ)
-#define USECS_PER_JIFFY_FRAC ((u32)((1000000ULL << 32) / HZ))
+/*
+ * The integer part of the number of usecs per jiffy is taken from tick,
+ * but the fractional part is not recorded, so we calculate it using the
+ * initial value of HZ.  This aids systems where tick isn't really an
+ * integer (e.g. for HZ = 128).
+ */
+#define USECS_PER_JIFFY		tick
+#define USECS_PER_JIFFY_FRAC	((unsigned long)(u32)((1000000ULL << 32) / HZ))
 
 /*
  * forward reference
@@ -38,11 +46,14 @@
 extern rwlock_t xtime_lock;
 extern volatile unsigned long wall_jiffies;
 
+spinlock_t rtc_lock = SPIN_LOCK_UNLOCKED;
+
 /*
  * whether we emulate local_timer_interrupts for SMP machines.
  */
 int emulate_local_timer_interrupt;
 
+
 /*
  * By default we provide the null RTC ops
  */
@@ -58,6 +69,85 @@
 
 unsigned long (*rtc_get_time)(void) = null_rtc_get_time;
 int (*rtc_set_time)(unsigned long) = null_rtc_set_time;
+int (*rtc_set_mmss)(unsigned long);
+
+
+/* usecs per counter cycle, shifted to left by 32 bits */
+static unsigned int sll32_usecs_per_cycle;
+
+/* how many counter cycles in a jiffy */
+static unsigned long cycles_per_jiffy;
+
+/* Cycle counter value at the previous timer interrupt.. */
+static unsigned int timerhi, timerlo;
+
+/* expirelo is the count value for next CPU timer interrupt */
+static unsigned int expirelo;
+
+
+/*
+ * Null timer ack for systems not needing one (e.g. i8254).
+ */
+static void null_timer_ack(void) { /* nothing */ }
+
+/*
+ * Null high precision timer functions for systems lacking one.
+ */
+static unsigned int null_hpt_read(void)
+{
+	return 0;
+}
+
+static void null_hpt_init(unsigned int count) { /* nothing */ }
+
+
+/*
+ * Timer ack for a R4k-compatible timer of a known frequency.
+ */
+static void c0_fixed_timer_ack(void)
+{
+	unsigned int count;
+
+	/* Ack this timer interrupt and set the next one.  */
+	expirelo += cycles_per_jiffy;
+	write_c0_compare(expirelo);
+
+	/* Check to see if we have missed any timer interrupts.  */
+	count = read_c0_count();
+	if ((count - expirelo) < 0x7fffffff) {
+		/* missed_timer_count++; */
+		expirelo = count + cycles_per_jiffy;
+		write_c0_compare(expirelo);
+	}
+}
+
+/*
+ * High precision timer functions for a R4k-compatible timer.
+ */
+static unsigned int c0_hpt_read(void)
+{
+	return read_c0_count();
+}
+
+/* For unknown frequency.  */
+static void c0_hpt_init(unsigned int count)
+{
+	write_c0_count(read_c0_count() - count);
+}
+
+/* For a known frequency.  Used as an interrupt source.  */
+static void c0_fixed_hpt_init(unsigned int count)
+{
+	expirelo = cycles_per_jiffy;
+	count = read_c0_count() - count;
+	write_c0_count(0);
+	write_c0_compare(cycles_per_jiffy);
+	write_c0_count(count);
+}
+
+void (*mips_timer_ack)(void);
+unsigned int (*mips_hpt_read)(void);
+void (*mips_hpt_init)(unsigned int);
 
 
 /*
@@ -65,22 +155,23 @@
  */
 void do_gettimeofday(struct timeval *tv)
 {
-	unsigned long flags;
+	unsigned long flags, lost;
+
+	read_lock_irqsave(&xtime_lock, flags);
 
-	read_lock_irqsave (&xtime_lock, flags);
 	*tv = xtime;
 	tv->tv_usec += do_gettimeoffset();
-
 	/*
-	 * xtime is atomically updated in timer_bh. jiffies - wall_jiffies
-	 * is nonzero if the timer bottom half hasnt executed yet.
+	 * xtime is atomically updated in timer_bh.  jiffies - wall_jiffies
+	 * is nonzero if the timer bottom half hasn't executed yet.
 	 */
-	if (jiffies - wall_jiffies)
-		tv->tv_usec += USECS_PER_JIFFY;
+	lost = jiffies - wall_jiffies;
+	if (lost)
+		tv->tv_usec += lost * USECS_PER_JIFFY;
 
-	read_unlock_irqrestore (&xtime_lock, flags);
+	read_unlock_irqrestore(&xtime_lock, flags);
 
-	if (tv->tv_usec >= 1000000) {
+	while (tv->tv_usec >= 1000000) {
 		tv->tv_usec -= 1000000;
 		tv->tv_sec++;
 	}
@@ -88,27 +179,29 @@
 
 void do_settimeofday(struct timeval *tv)
 {
-	write_lock_irq (&xtime_lock);
+	write_lock_irq(&xtime_lock);
 
-	/* This is revolting. We need to set the xtime.tv_usec
-	 * correctly. However, the value in this location is
-	 * is value at the last tick.
-	 * Discover what correction gettimeofday
-	 * would have done, and then undo it!
+	/*
+	 * This is revolting.  We need to set "xtime" correctly.  However,
+	 * the value in this location is the value at the most recent update
+	 * of wall time.  Discover what correction gettimeofday() would have
+	 * done, and then undo it!
 	 */
 	tv->tv_usec -= do_gettimeoffset();
+	tv->tv_usec -= (jiffies - wall_jiffies) * USECS_PER_JIFFY;
 
-	if (tv->tv_usec < 0) {
+	while (tv->tv_usec < 0) {
 		tv->tv_usec += 1000000;
 		tv->tv_sec--;
 	}
+
 	xtime = *tv;
 	time_adjust = 0;			/* stop active adjtime() */
 	time_status |= STA_UNSYNC;
 	time_maxerror = NTP_PHASE_LIMIT;
 	time_esterror = NTP_PHASE_LIMIT;
 
-	write_unlock_irq (&xtime_lock);
+	write_unlock_irq(&xtime_lock);
 }
 
 
@@ -119,76 +212,61 @@
  * If the exact CPU counter frequency is known, use fixed_rate_gettimeoffset.
  * Otherwise use calibrate_gettimeoffset()
  *
- * If the CPU does not have counter register all, you can either supply
- * your own gettimeoffset() routine, or use null_gettimeoffset() routines,
- * which gives the same resolution as HZ.
+ * If the CPU does not have the counter register, you can either supply
+ * your own gettimeoffset() routine, or use null_gettimeoffset(), which
+ * gives the same resolution as HZ.
  */
 
+static unsigned long null_gettimeoffset(void)
+{
+	return 0;
+}
 
-/* This is for machines which generate the exact clock. */
-#define USECS_PER_JIFFY (1000000/HZ)
-
-/* usecs per counter cycle, shifted to left by 32 bits */
-static unsigned int sll32_usecs_per_cycle=0;
-
-/* how many counter cycles in a jiffy */
-static unsigned long cycles_per_jiffy=0;
-
-/* Cycle counter value at the previous timer interrupt.. */
-static unsigned int timerhi, timerlo;
-
-/* last time when xtime and rtc are sync'ed up */
-static long last_rtc_update;
 
-/* the function pointer to one of the gettimeoffset funcs*/
+/* The function pointer to one of the gettimeoffset funcs.  */
 unsigned long (*do_gettimeoffset)(void) = null_gettimeoffset;
 
-unsigned long null_gettimeoffset(void)
-{
-	return 0;
-}
 
-unsigned long fixed_rate_gettimeoffset(void)
+static unsigned long fixed_rate_gettimeoffset(void)
 {
 	u32 count;
 	unsigned long res;
 
 	/* Get last timer tick in absolute kernel time */
-	count = read_32bit_cp0_register(CP0_COUNT);
+	count = mips_hpt_read();
 
 	/* .. relative to previous jiffy (32 bits is enough) */
 	count -= timerlo;
 
-	__asm__("multu\t%1,%2\n\t"
-	        "mfhi\t%0"
-	        :"=r" (res)
-	        :"r" (count),
-	         "r" (sll32_usecs_per_cycle));
+	__asm__("multu	%1,%2"
+		: "=h" (res)
+		: "r" (count), "r" (sll32_usecs_per_cycle)
+		: "lo", "accum");
 
 	/*
 	 * Due to possible jiffies inconsistencies, we need to check
 	 * the result so that we'll get a timer that is monotonic.
 	 */
 	if (res >= USECS_PER_JIFFY)
-		res = USECS_PER_JIFFY-1;
+		res = USECS_PER_JIFFY - 1;
 
 	return res;
 }
 
+
 /*
- * Cached "1/(clocks per usec)*2^32" value.
+ * Cached "1/(clocks per usec) * 2^32" value.
  * It has to be recalculated once each jiffy.
  */
 static unsigned long cached_quotient;
 
 /* Last jiffy when calibrate_divXX_gettimeoffset() was called. */
-static unsigned long last_jiffies = 0;
-
+static unsigned long last_jiffies;
 
 /*
- * This is copied from dec/time.c:do_ioasic_gettimeoffset() by Mercij.
+ * This is moved from dec/time.c:do_ioasic_gettimeoffset() by Maciej.
  */
-unsigned long calibrate_div32_gettimeoffset(void)
+static unsigned long calibrate_div32_gettimeoffset(void)
 {
 	u32 count;
 	unsigned long res, tmp;
@@ -204,20 +282,21 @@
 			unsigned long r0;
 			do_div64_32(r0, timerhi, timerlo, tmp);
 			do_div64_32(quotient, USECS_PER_JIFFY,
-			            USECS_PER_JIFFY_FRAC, r0);
+				    USECS_PER_JIFFY_FRAC, r0);
 			cached_quotient = quotient;
 		}
 	}
 
 	/* Get last timer tick in absolute kernel time */
-	count = read_32bit_cp0_register(CP0_COUNT);
+	count = mips_hpt_read();
 
 	/* .. relative to previous jiffy (32 bits is enough) */
 	count -= timerlo;
 
-	__asm__("multu  %2,%3"
-	        : "=l" (tmp), "=h" (res)
-	        : "r" (count), "r" (quotient));
+	__asm__("multu  %1,%2"
+		: "=h" (res)
+		: "r" (count), "r" (quotient)
+		: "lo", "accum");
 
 	/*
 	 * Due to possible jiffies inconsistencies, we need to check
@@ -229,7 +308,7 @@
 	return res;
 }
 
-unsigned long calibrate_div64_gettimeoffset(void)
+static unsigned long calibrate_div64_gettimeoffset(void)
 {
 	u32 count;
 	unsigned long res, tmp;
@@ -239,54 +318,56 @@
 
 	quotient = cached_quotient;
 
-	if (tmp && last_jiffies != tmp) {
+	if (last_jiffies != tmp) {
 		last_jiffies = tmp;
-		__asm__(".set\tnoreorder\n\t"
-	        ".set\tnoat\n\t"
-	        ".set\tmips3\n\t"
-	        "lwu\t%0,%2\n\t"
-	        "dsll32\t$1,%1,0\n\t"
-	        "or\t$1,$1,%0\n\t"
-	        "ddivu\t$0,$1,%3\n\t"
-	        "mflo\t$1\n\t"
-	        "dsll32\t%0,%4,0\n\t"
-	        "nop\n\t"
-	        "ddivu\t$0,%0,$1\n\t"
-	        "mflo\t%0\n\t"
-	        ".set\tmips0\n\t"
-	        ".set\tat\n\t"
-	        ".set\treorder"
-	        :"=&r" (quotient)
-	        :"r" (timerhi),
-	         "m" (timerlo),
-	         "r" (tmp),
-	         "r" (USECS_PER_JIFFY));
-	        cached_quotient = quotient;
+		if (last_jiffies) {
+			unsigned long r0;
+			__asm__(".set	push\n\t"
+				".set	mips3\n\t"
+				"lwu	%0,%3\n\t"
+				"dsll32	%1,%2,0\n\t"
+				"or	%1,%1,%0\n\t"
+				"ddivu	$0,%1,%4\n\t"
+				"dsll32	%0,%5,0\n\t"
+				"or	%0,%0,%6\n\t"
+				"mflo	%1\n\t"
+				"ddivu	$0,%0,%1\n\t"
+				"mflo	%0\n\t"
+				".set	pop"
+				: "=&r" (quotient), "=&r" (r0)
+				: "r" (timerhi), "m" (timerlo),
+				  "r" (tmp), "r" (USECS_PER_JIFFY),
+				  "r" (USECS_PER_JIFFY_FRAC)
+				: "hi", "lo", "accum");
+			cached_quotient = quotient;
+		}
 	}
 
 	/* Get last timer tick in absolute kernel time */
-	count = read_32bit_cp0_register(CP0_COUNT);
+	count = mips_hpt_read();
 
 	/* .. relative to previous jiffy (32 bits is enough) */
 	count -= timerlo;
 
-	__asm__("multu\t%1,%2\n\t"
-	        "mfhi\t%0"
-	        :"=r" (res)
-	        :"r" (count),
-	         "r" (quotient));
+	__asm__("multu	%1,%2"
+		: "=h" (res)
+		: "r" (count), "r" (quotient)
+		: "lo", "accum");
 
 	/*
 	 * Due to possible jiffies inconsistencies, we need to check
 	 * the result so that we'll get a timer that is monotonic.
 	 */
 	if (res >= USECS_PER_JIFFY)
-		res = USECS_PER_JIFFY-1;
+		res = USECS_PER_JIFFY - 1;
 
 	return res;
 }
 
 
+/* last time when xtime and rtc are sync'ed up */
+static long last_rtc_update;
+
 /*
  * local_timer_interrupt() does profiling and process accounting
  * on a per-CPU basis.
@@ -299,7 +380,7 @@
  */
 void local_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 {
-	if(!user_mode(regs)) {
+	if (!user_mode(regs)) {
 		if (prof_buffer && current->pid) {
 			extern int _stext;
 			unsigned long pc = regs->cp0_epc;
@@ -311,44 +392,32 @@
 			 * put them into the last histogram slot, so if
 			 * present, they will show up as a sharp peak.
 			 */
-			if (pc > prof_len-1)
-			pc = prof_len-1;
+			if (pc > prof_len - 1)
+				pc = prof_len - 1;
 			atomic_inc((atomic_t *)&prof_buffer[pc]);
 		}
 	}
 
-#if defined(CONFIG_SMP)
+#ifdef CONFIG_SMP
 	/* in UP mode, update_process_times() is invoked by do_timer() */
 	update_process_times(user_mode(regs));
 #endif
 }
 
 /*
- * high-level timer interrupt service routines.  This function
+ * High-level timer interrupt service routines.  This function
  * is set as irqaction->handler and is invoked through do_IRQ.
  */
 void timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 {
-	if (mips_cpu.options & MIPS_CPU_COUNTER) {
-		unsigned int count;
+	unsigned int count;
 
-		/*
-		 * The cycle counter is only 32 bit which is good for about
-		 * a minute at current count rates of upto 150MHz or so.
-		 */
-		count = read_32bit_cp0_register(CP0_COUNT);
-		timerhi += (count < timerlo);   /* Wrap around */
-		timerlo = count;
+	count = mips_hpt_read();
+	mips_timer_ack();
 
-		/*
-		 * set up for next timer interrupt - no harm if the machine
-		 * is using another timer interrupt source.
-		 * Note that writing to COMPARE register clears the interrupt
-		 */
-		write_32bit_cp0_register (CP0_COMPARE,
-					  count + cycles_per_jiffy);
-
-	}
+	/* Update timerhi/timerlo for intra-jiffy calibration. */
+	timerhi += count < timerlo;			/* Wrap around */
+	timerlo = count;
 
 	/*
 	 * call the generic timer interrupt handling
@@ -360,27 +429,28 @@
 	 * CMOS clock accordingly every ~11 minutes. rtc_set_time() has to be
 	 * called as close as possible to 500 ms before the new second starts.
 	 */
-	read_lock (&xtime_lock);
+	read_lock(&xtime_lock);
 	if ((time_status & STA_UNSYNC) == 0 &&
 	    xtime.tv_sec > last_rtc_update + 660 &&
 	    xtime.tv_usec >= 500000 - ((unsigned) tick) / 2 &&
 	    xtime.tv_usec <= 500000 + ((unsigned) tick) / 2) {
-		if (rtc_set_time(xtime.tv_sec) == 0) {
+		if (rtc_set_mmss(xtime.tv_sec) == 0) {
 			last_rtc_update = xtime.tv_sec;
 		} else {
-			last_rtc_update = xtime.tv_sec - 600;
 			/* do it again in 60 s */
+			last_rtc_update = xtime.tv_sec - 600;
 		}
 	}
-	read_unlock (&xtime_lock);
+	read_unlock(&xtime_lock);
 
 	/*
-	 * If jiffies has overflowed in this timer_interrupt we must
+	 * If jiffies has overflown in this timer_interrupt, we must
 	 * update the timer[hi]/[lo] to make fast gettimeoffset funcs
 	 * quotient calc still valid. -arca
 	 */
 	if (!jiffies) {
 		timerhi = timerlo = 0;
+		mips_hpt_init(count);
 	}
 
 #if !defined(CONFIG_SMP)
@@ -391,7 +461,7 @@
 	 * In SMP mode, local_timer_interrupt() is invoked by appropriate
 	 * low-level local timer interrupt handler.
 	 */
-	local_timer_interrupt(0, NULL, regs);
+	local_timer_interrupt(irq, dev_id, regs);
 
 #else	/* CONFIG_SMP */
 
@@ -458,73 +528,92 @@
  *	c) enable the timer interrupt
  */
 
-void (*board_time_init)(void) = NULL;
-void (*board_timer_setup)(struct irqaction *irq) = NULL;
+void (*board_time_init)(void);
+void (*board_timer_setup)(struct irqaction *irq);
 
-unsigned int mips_counter_frequency = 0;
+unsigned int mips_counter_frequency;
 
 static struct irqaction timer_irqaction = {
-	timer_interrupt,
-	SA_INTERRUPT,
-	0,
-	"timer",
-	NULL,
-	NULL};
+	.handler = timer_interrupt,
+	.flags = SA_INTERRUPT,
+	.name = "timer",
+};
 
 void __init time_init(void)
 {
 	if (board_time_init)
 		board_time_init();
 
+	if (!rtc_set_mmss)
+		rtc_set_mmss = rtc_set_time;
+
 	xtime.tv_sec = rtc_get_time();
 	xtime.tv_usec = 0;
 
-	/* choose appropriate gettimeoffset routine */
-	if (!(mips_cpu.options & MIPS_CPU_COUNTER)) {
-		/* no cpu counter - sorry */
-		do_gettimeoffset = null_gettimeoffset;
-	} else if (mips_counter_frequency != 0) {
-		/* we have cpu counter and know counter frequency! */
-		do_gettimeoffset = fixed_rate_gettimeoffset;
-	} else if ((mips_cpu.isa_level == MIPS_CPU_ISA_M32) ||
-		   (mips_cpu.isa_level == MIPS_CPU_ISA_I) ||
-		   (mips_cpu.isa_level == MIPS_CPU_ISA_II) ) {
-		/* we need to calibrate the counter but we don't have
-		 * 64-bit division. */
-		do_gettimeoffset = calibrate_div32_gettimeoffset;
+	/* Choose appropriate high precision timer routines.  */
+	if (!cpu_has_counter && !mips_hpt_read) {
+		/* No high precision timer -- sorry.  */
+		mips_hpt_read = null_hpt_read;
+		mips_hpt_init = null_hpt_init;
+	} else if (!mips_counter_frequency) {
+		/* A high precision timer of unknown frequency.  */
+		if (!mips_hpt_read) {
+			/* No external high precision timer -- use R4k.  */
+			mips_hpt_read = c0_hpt_read;
+			mips_hpt_init = c0_hpt_init;
+		}
+
+		if ((current_cpu_data.isa_level == MIPS_CPU_ISA_M32) ||
+			 (current_cpu_data.isa_level == MIPS_CPU_ISA_I) ||
+			 (current_cpu_data.isa_level == MIPS_CPU_ISA_II))
+			/*
+			 * We need to calibrate the counter but we don't have
+			 * 64-bit division.
+			 */
+			do_gettimeoffset = calibrate_div32_gettimeoffset;
+		else
+			/*
+			 * We need to calibrate the counter but we *do* have
+			 * 64-bit division.
+			 */
+			do_gettimeoffset = calibrate_div64_gettimeoffset;
 	} else {
-		/* we need to calibrate the counter but we *do* have
-		 * 64-bit division. */
-		do_gettimeoffset = calibrate_div64_gettimeoffset;
-	}
+		/* We know counter frequency! */
+		if (!mips_hpt_read) {
+			/* No external high precision timer -- use R4k.  */
+			mips_hpt_read = c0_hpt_read;
+			mips_hpt_init = c0_fixed_hpt_init;
+
+			if (!mips_timer_ack)
+				/* R4k timer interrupt ack.  */
+				mips_timer_ack = c0_fixed_timer_ack;
+		}
 
-	/* caclulate cache parameters */
-	if (mips_counter_frequency) {
-		u32 count;
+		do_gettimeoffset = fixed_rate_gettimeoffset;
 
+		/* Calculate cache parameters.  */
 		cycles_per_jiffy = mips_counter_frequency / HZ;
 
-		/* sll32_usecs_per_cycle = 10^6 * 2^32 / mips_counter_freq */
-		/* any better way to do this? */
+		/* sll32_usecs_per_cycle = 10^6 * 2^32 / mips_counter_freq  */
+		/* Any better way to do this?  */
 		sll32_usecs_per_cycle = mips_counter_frequency / 100000;
 		sll32_usecs_per_cycle = 0xffffffff / sll32_usecs_per_cycle;
 		sll32_usecs_per_cycle *= 10;
-
-		/*
-		 * For those using cpu counter as timer,  this sets up the
-		 * first interrupt
-		 */
-		count = read_32bit_cp0_register(CP0_COUNT);
-		write_32bit_cp0_register (CP0_COMPARE,
-					  count + cycles_per_jiffy);
 	}
 
+	if (!mips_timer_ack)
+		/* No timer interrupt ack (e.g. i8254).  */
+		mips_timer_ack = null_timer_ack;
+
+	/* This sets up the high precision timer for the first interrupt.  */
+	mips_hpt_init(mips_hpt_read());
+
 	/*
 	 * Call board specific timer interrupt setup.
 	 *
 	 * this pointer must be setup in machine setup routine.
 	 *
-	 * Even if the machine choose to use low-level timer interrupt,
+	 * Even if a machine chooses to use a low-level timer interrupt,
 	 * it still needs to setup the timer_irqaction.
 	 * In that case, it might be better to set timer_irqaction.handler
 	 * to be NULL function so that we are sure the high-level code
@@ -537,15 +626,15 @@
 #define STARTOFTIME		1970
 #define SECDAY			86400L
 #define SECYR			(SECDAY * 365)
-#define leapyear(year)		((year) % 4 == 0)
-#define days_in_year(a)		(leapyear(a) ? 366 : 365)
-#define days_in_month(a)	(month_days[(a) - 1])
+#define leapyear(y)		((!((y) % 4) && ((y) % 100)) || !((y) % 400))
+#define days_in_year(y)		(leapyear(y) ? 366 : 365)
+#define days_in_month(m)	(month_days[(m) - 1])
 
 static int month_days[12] = {
 	31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
 };
 
-void to_tm(unsigned long tim, struct rtc_time * tm)
+void to_tm(unsigned long tim, struct rtc_time *tm)
 {
 	long hms, day, gday;
 	int i;
@@ -560,16 +649,16 @@
 
 	/* Number of years in days */
 	for (i = STARTOFTIME; day >= days_in_year(i); i++)
-	day -= days_in_year(i);
+		day -= days_in_year(i);
 	tm->tm_year = i;
 
 	/* Number of months in days left */
 	if (leapyear(tm->tm_year))
-	days_in_month(FEBRUARY) = 29;
+		days_in_month(FEBRUARY) = 29;
 	for (i = 1; day >= days_in_month(i); i++)
-	day -= days_in_month(i);
+		day -= days_in_month(i);
 	days_in_month(FEBRUARY) = 28;
-	tm->tm_mon = i-1;	/* tm_mon starts from 0 to 11 */
+	tm->tm_mon = i - 1;		/* tm_mon starts from 0 to 11 */
 
 	/* Days are what is left over (+1) from all that. */
 	tm->tm_mday = day + 1;
@@ -577,5 +666,10 @@
 	/*
 	 * Determine the day of week
 	 */
-	tm->tm_wday = (gday + 4) % 7; /* 1970/1/1 was Thursday */
+	tm->tm_wday = (gday + 4) % 7;	/* 1970/1/1 was Thursday */
 }
+
+EXPORT_SYMBOL(rtc_lock);
+EXPORT_SYMBOL(to_tm);
+EXPORT_SYMBOL(rtc_set_time);
+EXPORT_SYMBOL(rtc_get_time);
FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)